Vehicles, particularly commercial air, marine and land vehicles, typically include some type of performance monitoring system that records data regarding the vehicle performance, which includes the performance of the various systems and subsystems of the vehicle. The data include a record of certain performance events that occur during the operation of the vehicle. The performance monitoring system typically conducts data collection and reports all of the data collected to the user. The user then may utilize the data in determining the type of maintenance, if any, that the vehicle may need. For example, if the data indicate that a particular component of the vehicle is malfunctioning or that the performance of one or more components may contribute to a vehicle failure in the future, then the user can perform the appropriate maintenance on the vehicle at the next opportunity.
For example, an air vehicle typically has a central maintenance computer (CMC). The CMC collects, consolidates and reports performance data for the components of the air vehicle. Certain maintenance messages (MMSGs) are associated with one or more types of performance data, and are stored in the CMC. Thus, when the CMC receives performance data, it analyzes the data to determine if the received data meets the criteria associated with the maintenance messages. If the received data meet the criteria, then the CMC presents the appropriate stored maintenance message to the user via a user interface. A CMC is further described, for example, in U.S. Pat. No. 4,943,919 entitled, “Central Maintenance Computer System and Fault Data Handling Method.”
Certain events on an aircraft trigger Flight Deck Effects (FDEs). FDEs result when a system or subsystem failure, or other fault, causes a problem with the aircraft that may affect airworthiness. In addition to the maintenance messages collected by the CMC, as discussed above, information regarding FDEs are also collected by the CMC. Unlike maintenance messages, which are only viewed by maintenance personnel, FDEs are broadcast to the flight deck of the air vehicle to alert the flight crew. Some FDEs require immediate action by the flight crew to remedy the problem, such as returning to the origin airport (this is called an air turn-back) or diverting the flight to a different airport than the original destination (this is called a diversion) so the problem can be fixed. Some FDEs do not affect the current flight on which the FDE occurs, but rather require immediate maintenance at the destination airport. This need for immediate maintenance can therefore cause a delay or a cancellation of the next flight that the vehicle was scheduled to make. Some FDEs do not require in-flight action or immediate maintenance, but rather may merely require maintenance within a few days of the FDE first occurring. Whether an FDE requires immediate or delayed maintenance is typically dictated by the airline's Minimum Equipment List (MEL). An MEL permits operation of an aircraft under specified conditions with inoperative equipment. An MEL applies to an airline's particular aircraft configuration, operational procedures, and conditions. Whether an aircraft can operate, and for how long, with an FDE is described as MEL dispatch relief. For example, an FDE that requires immediate maintenance (i.e., the aircraft cannot fly again until the FDE is resolved) is described as having no MEL dispatch relief. Other FDEs may have varying levels of MEL dispatch relief.
While the current system(s) utilized for vehicle performance and fault monitoring provide the necessary data for a user to make an appropriate maintenance decision, it is still necessary for a user to sort through all of the data and maintenance messages to determine what type of maintenance is necessary. Thus, the user must sort and interpret the data provided by the monitoring system, such as the CMC for an air vehicle, in light of the user's knowledge of the particular maintenance plan for the vehicle. For example, one user may implement a conservative maintenance plan for its vehicles, and as such, that user may carry out a certain type of maintenance the first time a particular performance or fault event occurs during the operation of the vehicle. Another user, however, may wish to carry out a certain type of maintenance only if a particular performance or fault event occurs more than five times over a particular interval.
With the current monitoring systems, each user will be presented with the same performance and fault data, and the user must interpret it in light of their preferred maintenance plan, which is time consuming and dependent upon the user being familiar with the appropriate maintenance plan and any recent changes to the maintenance plan. For many types of vehicles, particularly commercial vehicles, the amount of time the vehicle is out of service is costly to the vehicle owner. As such, the longer it takes for a user to determine the type of maintenance that is necessary for a vehicle in accordance with the particular maintenance plan for the vehicle, the longer the vehicle will be out of service, which may be expensive to the vehicle owner if the vehicle would otherwise be in service.
Other monitoring systems include certain user customizable settings. For instance, some systems permit a user to specify alarm filtering and prioritization, and general alarm level triggers and thresholds. Thus, the data presented to the user will be associated with an alarm only if the data meet the criteria specified by the system. One example of such a system is disclosed in U.S. Patent Application Publication No. 2002/0163427 to Eryurek et al., which was published on Nov. 7, 2002. Further systems permit management of maintenance tasks based upon operational and scheduling preferences, such that the intervals between maintenance tasks may be increased or the tasks may be organized into groups. Examples of these systems are described in U.S. Pat. No. 6,442,459 to Sinex and U.S. Patent Application Publication No. 2002/0143445 to Sinex, which was published on Oct. 3, 2002. While these systems permit users to customize a performance monitoring system to some extent, they do not provide for the level of customization that is necessary to allow a user to implement a particular maintenance program based upon the user preferences. As such, although a user may be permitted to specify when and how alarms associated with the data are presented and/or when and how the user is notified of certain maintenance tasks in general, the systems do not allow a user to specify how the system interprets and presents particular type(s) of data. For example, the conventional monitoring systems would not permit a user to specify the number of times a particular performance event must occur during the operation of the vehicle before the user is notified that a particular type of maintenance is recommended.
One monitoring system which addresses many of the problems mentioned above is the system disclosed in co-pending U.S. Patent Application Publication No. 2004/0158367 entitled “Vehicle Monitoring and Reporting System and Method” by Basu et al., and published Aug. 12, 2004, which is incorporated herein by reference in its entirety. This monitoring system permits a user to implement a maintenance plan that fits a specific business plan for their vehicles by combining real-time vehicle performance data with specific user preferences for each potential type of data that is captured by the system. This system saves time and costs that are normally associated with a user interpreting all of the data provided by a vehicle monitoring and reporting system in light of a preferred maintenance plan, which is time consuming and dependent upon the user being familiar with the appropriate maintenance plan and any recent changes to the maintenance plan.
Current performance monitoring systems typically conduct data collection and report all of the data collected to the user. The user then may utilize the data in determining the type of maintenance that the vehicle may need. However, current systems can only wait for an FDE to occur, and then facilitate the appropriate maintenance to correct the FDE by utilizing the maintenance messages. Current systems do not allow for FDEs to be predicted and therefore avoided. If it were possible to discern a predictive relationship between the maintenance message data and the occurrence of FDEs, it may be possible to prevent FDEs by performing maintenance before the failure occurs. For example, if the maintenance message data indicate that one or more subsystems may fail in the near future, then the user can perform the appropriate maintenance on the vehicle at the next opportunity. The appropriate maintenance may include repair or replacement of the subsystem that is predicted to fail. Without the ability to predict subsystem failure, repair or replacement is not conducted until failure occurs. Waiting until failure occurs, particularly when the vehicle is an air vehicle, risks costly delays and cancellations in the scheduled use of the vehicle as well as other more serious consequences such as air turn-backs and diversions.
The system disclosed in U.S. Patent Application Publication No. 2004/0158367 by Basu et al. receives data, which may be fault data and/or prognostic data, associated with operation of the vehicle, via a data gathering element. In addition, at least one user preference may be applied to the data, such as via a customization element, and at least a portion of the data may be presented, such as via a display element. The data gathering element may be located within the vehicle and the customization element may be located outside the vehicle, with a communication link between the two elements to transmit data between the data gathering element and the customization element. In other embodiments, the data gathering element may be located outside the vehicle, and a communication link between the data gathering element and the vehicle may be utilized to transmit data between the vehicle and the data gathering element. In further embodiments, the data gathering element and the customization element may be integrated.
In some embodiments of this system, the data may represent events associated with operation of the vehicle, and an alerting preference may be applied to alert the user once the data reflect that a maximum number of events have occurred. The data also may be consolidated and the probability of vehicle failure from the occurrence of an event over time may be determined, such as by a processing element. In addition, a prioritization preference may be applied to prioritize the data based upon a probability of vehicle failure after the occurrence of an event, where data associated with a higher probability of vehicle failure has a higher priority than data associated with a lower probability of vehicle failure. Prioritization preferences also may include directions for presenting data based upon the priority of the data. In this embodiment, the alerting preferences may include directions to alert the user, and the data delivery preferences may include directions to immediately deliver the data to the user when the probability of vehicle failure after the occurrence of an event in the data is at least a predetermined value.
U.S. Patent Application Publication No. 2004/0158367 by Basu et al. discloses a system whereby the probability of vehicle failure from the occurrence of an event over time may be determined. However, repairing or replacing subsystems based on predictions of future failure, as this system does, requires the ability to accurately predict failure. Without accurate predictions, subsystems are replaced sooner than necessary or subsystems that were not likely to fail are replaced. In either event, inaccurate predictions of failure needlessly increase maintenance costs. Alternatively, without accurate predictions of failure, a vehicle operator cannot prevent failure by performing maintenance before the failure occurs. This results in costly unscheduled interruptions. By accurately predicting when a subsystem may fail, the appropriate maintenance can be scheduled so as to minimize or eliminate delays, while also minimizing premature or unnecessary replacement of subsystems.
As such, there is a need for a system, method, and computer program product for predicting future failure of vehicle subsystems incorporated into vehicle monitoring and reporting systems such as the one disclosed by U.S. Patent Application Publication No. 2004/0158367 by Basu et al.